NASA’s Curiosity team has signed off on the newest drilling site for the Martian rover – and plans to stick its third ever hole on the planet into the Windjana rock in the next few days.

Dusted off area of the Windjana drilling target for Curiosity. Credit: NASA/JPL

The nuclear-powered truck has spent the weekend dusting off and examining its chosen target, dubbed Windjana, after a gorge in Western Australia, and the slab of sandstone has met with the scientific team’s approval.

"In the brushed spot, we can see that the rock is fine-grained, its true colour is much greyer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures," said team member Melissa Rice of the California Institute of Technology.

"All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock," she added.

Windjana is the first sandstone target for Curiosity’s drill, after two Martian mudstone slabs from Yellowknife Bay were analysed last year. The first two drilling sites gave teams evidence of an ancienet lakebed environment and a chemical energy source that provided conditions billions of years ago that were favourable for microbial life.

Boffins are hoping that investigating sandstone will tell them more about the wet process that turns sand deposits into rocks and what the composition of the fluids was that tied the grains together.

Before Curiosity can get drilling, it still needs to do its preparatory “mini-drill”operation, as a further check for readiness. The team expects the rover to start the main borehole in the next few days to collect powdered sample material from the interior of the rock. ®